Life on Mars—A Journey to the Red Planet!

Greetings, future astronauts, and scientists! Are you ready to embark on an out-of-this-world adventure as we delve into the captivating realm of life on Mars? Joint us as we explore the mysteries of the Red Planet, envisioning a future where humans might one day call Mars their home. So, strap on your spacesuits, fasten your seatbelts, and let’s launch into a thrilling exploration of finding life on the mysterious and captivating planet of Mars!

We all know that NASA’s rovers have been searching for signs of ancient life on the Red Planet. They analyze rocks by looking at closeups of tiny segments of rock surfaces that might show evidence of past microbial activity. Early closeups have already yielded a trove of data from Martian rocks—such as a variety of colors, sizes of grains in the sediment, and even the presence of “cement” between the grains. Such details can provide important clues about formation history, water flow, and ancient, potentially habitable Martian environments.

A key objective for the current mission on Mars is astrobiology, including the search for signs of ancient microbial life. The current rovers will characterize the planet’s geology and past climate, pave the way for human exploration of the Red Planet, and be the first missions to collect and cache Martian rock and regolith (broken rock and dust).

Astrobiology is the branch of biology concerned with the study of life on earth and in space.

Subsequent NASA missions, in cooperation with ESA (European Space Agency), would send spacecraft to Mars to collect these sealed samples from the surface and return them to Earth for in-depth analysis.

The possibility of life on Mars is a subject of interest in astrobiology because of the planet’s proximity and similarities to Earth. Scientists have found no proof of past or present life on Mars yet. Cumulative evidence suggests that in the past, the surface environment of Mars had liquid water and may have been habitable for microorganisms, but habitable conditions do not necessarily indicate life.

Mars is of particular interest for the study of the presence of early life because of its similarity to the early Earth. This is especially true since Mars has a cold climate and lacks plate tectonics or continental drift, so it has remained almost unchanged since the end of the Hesperian period. At least two-thirds of Mars’ surface is over 3.5 billion years old, and it could have been habitable since 4.48 billions of years ago, 500 million years before the earliest known Earth lifeforms. Mars may thus hold the best record of the prebiotic conditions leading to life, even if life does not or has never existed there.

The Hesperian is a geologic system and time period on the planet Mars characterized by widespread volcanic activity and catastrophic flooding that carved immense outflow channels across the surface. During the Hesperian, Mars changed from the wetter and perhaps warmer world of the Noachian to the dry, cold, and dusty planet seen today. The Hesperian Period is roughly coincident with the Earth’s early Archean Eon (4,000 to 2,500 million years ago).

The Noachian is a geologic system and early time period on Mars, characterized by high rates of meteorite and asteroid impacts and the possible presence of abundant surface water. The absolute age of the Noachian period is uncertain but probably corresponds to the lunar Pre-Nectarian to Early Imbrian periods of 4100 to 3700 million years ago, during the interval known as the Late Heavy Bombardment.

Many of the large impact basins on the Moon and Mars formed at this time. The Noachian Period is roughly equivalent to the Earth’s Hadean and early Archean eons when the first life forms likely arose. It spans 400 million years, from the end of the Hadean Eon 4 billion years ago.

While we have not found life on Mars so far, that does not mean it did not exist. Who knows? Maybe someday in the future you just might be a scientist or engineer or computer expert who helps solve that mystery.

AIME